//all为总页数，now为当前页数
function pages(all,now){
    let number_w=document.querySelector('.number_w')
    let left_w=document.querySelector('.left_w')
    let right_w=document.querySelector('.right_w')
    if(all!=0){
        number_w.style.visibility='initial'
    }else{
        number_w.style.visibility='hidden'
    }

    if(now!=1){
        left_w.style.visibility='initial'
    }else{
        left_w.style.visibility='hidden'
    }

    if(now!=all){
        right_w.style.visibility='initial'
    }else{
        right_w.style.visibility='hidden'
    }
    if(now<0){
        now=1
    }
    if(now>all){
        now=all
    }
    number_w.innerHTML=now
}